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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/common/dwarf/bytereader.cc')
-rw-r--r--toolkit/crashreporter/google-breakpad/src/common/dwarf/bytereader.cc250
1 files changed, 0 insertions, 250 deletions
diff --git a/toolkit/crashreporter/google-breakpad/src/common/dwarf/bytereader.cc b/toolkit/crashreporter/google-breakpad/src/common/dwarf/bytereader.cc
deleted file mode 100644
index 14b43adb8..000000000
--- a/toolkit/crashreporter/google-breakpad/src/common/dwarf/bytereader.cc
+++ /dev/null
@@ -1,250 +0,0 @@
-// Copyright (c) 2010 Google Inc. All Rights Reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-// * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-// * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-// * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include <assert.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include "common/dwarf/bytereader-inl.h"
-#include "common/dwarf/bytereader.h"
-
-namespace dwarf2reader {
-
-ByteReader::ByteReader(enum Endianness endian)
- :offset_reader_(NULL), address_reader_(NULL), endian_(endian),
- address_size_(0), offset_size_(0),
- have_section_base_(), have_text_base_(), have_data_base_(),
- have_function_base_() { }
-
-ByteReader::~ByteReader() { }
-
-void ByteReader::SetOffsetSize(uint8 size) {
- offset_size_ = size;
- assert(size == 4 || size == 8);
- if (size == 4) {
- this->offset_reader_ = &ByteReader::ReadFourBytes;
- } else {
- this->offset_reader_ = &ByteReader::ReadEightBytes;
- }
-}
-
-void ByteReader::SetAddressSize(uint8 size) {
- address_size_ = size;
- assert(size == 4 || size == 8);
- if (size == 4) {
- this->address_reader_ = &ByteReader::ReadFourBytes;
- } else {
- this->address_reader_ = &ByteReader::ReadEightBytes;
- }
-}
-
-uint64 ByteReader::ReadInitialLength(const uint8_t *start, size_t* len) {
- const uint64 initial_length = ReadFourBytes(start);
- start += 4;
-
- // In DWARF2/3, if the initial length is all 1 bits, then the offset
- // size is 8 and we need to read the next 8 bytes for the real length.
- if (initial_length == 0xffffffff) {
- SetOffsetSize(8);
- *len = 12;
- return ReadOffset(start);
- } else {
- SetOffsetSize(4);
- *len = 4;
- }
- return initial_length;
-}
-
-bool ByteReader::ValidEncoding(DwarfPointerEncoding encoding) const {
- if (encoding == DW_EH_PE_omit) return true;
- if (encoding == DW_EH_PE_aligned) return true;
- if ((encoding & 0x7) > DW_EH_PE_udata8)
- return false;
- if ((encoding & 0x70) > DW_EH_PE_funcrel)
- return false;
- return true;
-}
-
-bool ByteReader::UsableEncoding(DwarfPointerEncoding encoding) const {
- switch (encoding & 0x70) {
- case DW_EH_PE_absptr: return true;
- case DW_EH_PE_pcrel: return have_section_base_;
- case DW_EH_PE_textrel: return have_text_base_;
- case DW_EH_PE_datarel: return have_data_base_;
- case DW_EH_PE_funcrel: return have_function_base_;
- default: return false;
- }
-}
-
-uint64 ByteReader::ReadEncodedPointer(const uint8_t *buffer,
- DwarfPointerEncoding encoding,
- size_t *len) const {
- // UsableEncoding doesn't approve of DW_EH_PE_omit, so we shouldn't
- // see it here.
- assert(encoding != DW_EH_PE_omit);
-
- // The Linux Standards Base 4.0 does not make this clear, but the
- // GNU tools (gcc/unwind-pe.h; readelf/dwarf.c; gdb/dwarf2-frame.c)
- // agree that aligned pointers are always absolute, machine-sized,
- // machine-signed pointers.
- if (encoding == DW_EH_PE_aligned) {
- assert(have_section_base_);
-
- // We don't need to align BUFFER in *our* address space. Rather, we
- // need to find the next position in our buffer that would be aligned
- // when the .eh_frame section the buffer contains is loaded into the
- // program's memory. So align assuming that buffer_base_ gets loaded at
- // address section_base_, where section_base_ itself may or may not be
- // aligned.
-
- // First, find the offset to START from the closest prior aligned
- // address.
- uint64 skew = section_base_ & (AddressSize() - 1);
- // Now find the offset from that aligned address to buffer.
- uint64 offset = skew + (buffer - buffer_base_);
- // Round up to the next boundary.
- uint64 aligned = (offset + AddressSize() - 1) & -AddressSize();
- // Convert back to a pointer.
- const uint8_t *aligned_buffer = buffer_base_ + (aligned - skew);
- // Finally, store the length and actually fetch the pointer.
- *len = aligned_buffer - buffer + AddressSize();
- return ReadAddress(aligned_buffer);
- }
-
- // Extract the value first, ignoring whether it's a pointer or an
- // offset relative to some base.
- uint64 offset;
- switch (encoding & 0x0f) {
- case DW_EH_PE_absptr:
- // DW_EH_PE_absptr is weird, as it is used as a meaningful value for
- // both the high and low nybble of encoding bytes. When it appears in
- // the high nybble, it means that the pointer is absolute, not an
- // offset from some base address. When it appears in the low nybble,
- // as here, it means that the pointer is stored as a normal
- // machine-sized and machine-signed address. A low nybble of
- // DW_EH_PE_absptr does not imply that the pointer is absolute; it is
- // correct for us to treat the value as an offset from a base address
- // if the upper nybble is not DW_EH_PE_absptr.
- offset = ReadAddress(buffer);
- *len = AddressSize();
- break;
-
- case DW_EH_PE_uleb128:
- offset = ReadUnsignedLEB128(buffer, len);
- break;
-
- case DW_EH_PE_udata2:
- offset = ReadTwoBytes(buffer);
- *len = 2;
- break;
-
- case DW_EH_PE_udata4:
- offset = ReadFourBytes(buffer);
- *len = 4;
- break;
-
- case DW_EH_PE_udata8:
- offset = ReadEightBytes(buffer);
- *len = 8;
- break;
-
- case DW_EH_PE_sleb128:
- offset = ReadSignedLEB128(buffer, len);
- break;
-
- case DW_EH_PE_sdata2:
- offset = ReadTwoBytes(buffer);
- // Sign-extend from 16 bits.
- offset = (offset ^ 0x8000) - 0x8000;
- *len = 2;
- break;
-
- case DW_EH_PE_sdata4:
- offset = ReadFourBytes(buffer);
- // Sign-extend from 32 bits.
- offset = (offset ^ 0x80000000ULL) - 0x80000000ULL;
- *len = 4;
- break;
-
- case DW_EH_PE_sdata8:
- // No need to sign-extend; this is the full width of our type.
- offset = ReadEightBytes(buffer);
- *len = 8;
- break;
-
- default:
- abort();
- }
-
- // Find the appropriate base address.
- uint64 base;
- switch (encoding & 0x70) {
- case DW_EH_PE_absptr:
- base = 0;
- break;
-
- case DW_EH_PE_pcrel:
- assert(have_section_base_);
- base = section_base_ + (buffer - buffer_base_);
- break;
-
- case DW_EH_PE_textrel:
- assert(have_text_base_);
- base = text_base_;
- break;
-
- case DW_EH_PE_datarel:
- assert(have_data_base_);
- base = data_base_;
- break;
-
- case DW_EH_PE_funcrel:
- assert(have_function_base_);
- base = function_base_;
- break;
-
- default:
- abort();
- }
-
- uint64 pointer = base + offset;
-
- // Remove inappropriate upper bits.
- if (AddressSize() == 4)
- pointer = pointer & 0xffffffff;
- else
- assert(AddressSize() == sizeof(uint64));
-
- return pointer;
-}
-
-Endianness ByteReader::GetEndianness() const {
- return endian_;
-}
-
-} // namespace dwarf2reader
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-16 03:22:47 +0000